This project is designed to develop an effective isolation technique for pancreatic islets from animals larger than rodents, including man. The basic components of the isolation technique are being investigated for improving the yield of viable islet tissue. The method of distension is being examined with initial success demonstrated using venous distension to provide the improved intralobular disruption needed to permit more efficient collagenase release of intact islets. The collagenase enzyme system is also being examined in a digestion-filtration system. Centrifugation density gradients are being utilized for purification of the tissue for purposes of transplantation. The final basic goal of this work is an automated method for islet isolation providing a reliable source of viable islet tissue suitable for islet transplantation in man.